Signal system



Feb. 23-, 1926. 1,574,648

- J. L. HALL SIGNAL SYSTEM Filed Jan. 28, 1922 T552; B. i0

His fFb-horneg.

Patented Feb. 23, 1926.

UNITED STATES 1,574,648 PATENT. OFFICE.

Join; L. HALL, or

SCHEN ECTADY, NEW YORK, ASSIGNOB TO GENERAL ELECTRIC COHPANY, A COBPORATIOH OF NEW YORK. y

SIGNAL SYBTELI.

- Application filed January 28, 1922. Serial No. 582,882.

To all whom it may concern:

Be it known that 1, JOHN L. HALL, a citizen of the United States, residing at Schenectady, in the county of Schenectady, State of New York, have invented certain new and useful Improvements'in Signal Systems, of which the following is a specification.

My invention relates to signal systems and has for its object improvements in signal systems of the type described and claimed iligliny Patent No. 1,077,706, dated Nov. 4,

In my aforesaid patent I have.disclosed a signal system in which two continuously rotating shafts located respectively at the sending and receiving stations are provided. These shafts are automatically maintained in synchronism. One or more rotary indicators or drums are driven by the shaft in the receiving station through a yieldable operating connection. The indicator. may be arrested in any desired indicating position by means of a plurality of latches, each latc corresponding to .an indicating position. The latches are selectively actuated by means of an electromagnet which is controlled throu h contact mechanism driven by the shaft in the sending-station.

In carrying out my present invention, I employ a single locking member for arresting the indicator in its various positions, the locking member being operated b means of a suitable electromagnetj In one arm of my invention I operatively connect the indicator to the shaft in the receiving station so that it is always driven in a predetermined relation with said shaft. By means of selective switching means at the sending station, under the control of the rotating shaft in the sending station, I am enabledto energize the electromagnet so as to arrest the indicator when in position to give the desired indication. For a more complete understanding of my invention reference should be had to the accompanying drawing in which Fig. 1 shows in diagrammatic form a signal system embod ingmy invention; Fig. 2 is an elevation view of the indicator and driving means therefor; Fig. 3 is'an elevation view of the dial in the sending station by means of which the desired signals are selected;

while Fig. 4 is a plan view of the friction connection between. the shaft in the receiving station and its driving motor.

Referring to the drawing in one form of my invention the shafts 10 and 11, located in the sending and receiving statlons, respectivel are continuously rotated by means 0 electric driving motors 12 and 13. Motors 12 and 13 are referably of the type having a fairly uni orm speed, and are adapted to drive the shafts at equal speeds. The motors are operatively connected to the shafts, such as by worm gearing, as shown in the drawing. A yieldable or frictional driving connection is rovided between motor 13 and shaft 11, which consists of a clutch member 14 rigidly secured to the shaft and provided with a cone shaped clutch face 14 adapted to fit in a similar face 14: on worm wheel 15 in driving engagement with which is worm 16 secured to the shaft of the motor. Worm gear 15 is loosely mounted on the shaft and is held in engagement with the clutch member 14 with a certain predetermined pressure by means of a spiral s ring 17 placed between the worm gear an collar 18 secured to the shaft.

In order to synchronize shafts 10 and 11 and operate them in synchronism regardless of o erative variations in the speeds of the driving motors, I provide on shafts 10 and 11, in insulated relation therewith, circular circuit closers 20 and 21, and upon shaft 11 a disc member 22 carrying a detent or arm 23 adapted to engage as shaft 11 is rotated with a pivoted armature 24 which normally is held by a suitable spring in enga ment with the periphery of member 22. e contact closures, 20 and 21 consist of disc shaped pieces of suitable electrical conducting material provided with projections 25 and-26 and secured on the shafts in insulated relation therewith. Cooperating with each of the circuit closers is a pair of brushes, one of which is in engagement with the cir- 'cuit closer, while the other is ada ted to be engaged by the projection as t e circuit closer rotates with the shaft on which it is mounted so as to close a circuit between thetwo brushes once each revolution. Cooper- -ating with -armature 24 is an electromagnet 29 which is connected by suitable conductors to a source of electrical supply 30 in series with the two circuit closing devices. Projection 23 is adapted to engage armature 24 at the same time that circuit closer 21 short circuits its cooperating brushes, and should circuit closer 20 be in position at that time to complete the circuit through coil 29, then armature- 24 'will be attracted and shaft 11 maintained free to rotate without interruption. Under these conditions the two shafts are in synchronism.

Should, for any reason whatever, one of the shafts lag or lead the other, the two are automatically brought into synchronism by adjusting the rotation of shaft 11. it will be observed that when the shafts are not in synchronism, then the circuit closing devices 20 and 21 do not short circuit their brushes simultaneously and therefore shaft 11 will be arrested by the engagement of stop 23 with armature 24, worm gear meanwhile continuing its rotation under the influence or motor 13 by reason of the slip coupling. Shaft 11 will be held by the engagement of projection 23 with armature 24 until circuit closer completes the circuit through coil 29, whereupon shaft 11 will be released and the two shafts continue their rotation in synchronism -t will be observed that the shafts will be automatically synchronized whenever they get out of step and may be synchronized as often as once each revolution of shaft 11. I

Loosely mounted on shaft 11 is a otary indicator or drum 31. On the inner surface of the drum (Fig. 2) is a projection 32 adapted to engage with which is an arm 33 secured to shaft 11. Arm 33 is made in two parts, a part 34 which is secured to shaft 11, and a part 35 forming a latch pivotally secured near its middle to the end of part and held len thwise of part 34 by a spiral spring 33. y means of this arrangement the indicating drum is operated by shaft 11 upon the engagement of arm 33 with the projection in a predetermined angular re lat-ion with shaft 11. By means of a latch 37 adapted to engage stops or pins 38 secured to the drum, the drummay be arrested in its movement, member 35 on arm 33 then moving about its pivot against the bias of spring 36, allowing arm 33 to move by projection 32 Latch 37 is pivoted-pat 28 and its lower end forms an armature 39 cooperating with which is an electromagnet 40. The latch is normally held'out of the path of stops 38 by means of a spring 41 and is moved against the tension of spring 41 into engagement with the stops by electromagnet 40. Upon the outer surface of the drum, suitably spaced, are signaling characters shown in the drawing as numerals. Recesses 42 are provided in the periphery of the drum and adapted to fall successively in the recesses is a roller 43 secured to end of a resilient arm 44. The recesses are suitably spaced and placed with relation to the numerals so that when the roller 43 falls in one of the recesses, a numeral is in view through a sight opening or window 45 in the enclosing casing 46., The

Electromagnet 40 is selectively energized so as to stop the drum at any desired indicating position by means of contacts and 51 located at the sending station. Contact 50 is mounted on a resilient arm carried by a conducting disc 52 which is secured to shaft 10 in insulated relation therewith. It bears on a contact device 53., secured to a shaft 54 in insulated relation therewith. The contact device 53 comprises a conducting disc 55, the pe riphery of which is covered by insulating material 56 with the exception of an extension or projection forming contact 51. When contacts 50 and 51 are in engagement, a circuit for electromagnet 40 is closed lead ing from supply source 30 through c0n ductor 57, the electromagnet, conductor 58 and by way of a brush to conducting disc 55, contacts 50 and 51, conducting disc 52, and by way of a brush through conductor 59 back to the source of supply.- Shaft is provided on its end opposite coritact device 53 with a knob 60, by means of which the shaft may be turned, carrying a pointer 61. The pointer 61 cooperates with a stationary dial 62, spaced around the periphery'of which are signaling characters, shown as numerals, corresponding to the characters on the drum 31. It will be observed that when pointer 61 is turned by.

knob to designate any desired character, 54 is likewise rotated whereby the angular position of contact 51 is changed. As shaft 10 rotates carrying contact 50 with it, the circuit for electromagnet 41 is closed momentarily once each revolution by the engagement of contact 50 with adjustable contact 51.

As thus constructed and arranged, the operation of my invention is as follows:

Assuming that shafts 10 and 11 are rotating under the influence of motors 12 and 13, which may be energized from supply source 30 the synchronous rotation of the shafts being maintained as previously described by means of contact devices 20 and 21 and electromagnet 29, should it be desired to transmit a number from the sending station to the receiving station, knob 60 is-turned until pointer 61' designates this number on scale 62. In this manner contact 51 is given an adjustment corresponding to the number. Assuming that the desired number is numeral 1, when drum 31 reaches a position as it is rotated by shaft 11 to bring this numeral into view through the window 45, contact 50 will engage with contact 51 closing the circuit for the electromagnet 40. Upon the energization. of electromagnet 40,

it picks up its armature moving latch 37 in the path of a stop- 38 on druni 31, thus arresting the movement of the drum with numeral 1 in view, as shown in the drawing.

The relative widths of contacts 50 and 51 are such that the circuit of the electromagnet is maintained closed for a suiiicien't length of time to lock drum 31 until arm 33 passes projection 32. Upon continued movement of" contact it disengages contact 51, opening the circuit for electromagnet 40, the indicating drum 31 then being held in the adjusted position by means of spring pressed roller 43, and arm 33 continuing its rotary movement without affecting the position of the indicating drum. As arm 33 approaches projection 32 upon the completionof the next revolution of shaft 11, contact 50 will again engage contact 51 so as to lock the drum, as previously described, until arm 33'lias moved by projection 32. The drum' is thus held in its adjusted position until pointer 61 is moved to designate another numeral.

It will be observed that by providing a plurality of indicating drums and selective switching mechanisms any number of successive digits or characters may be transmitted.

While I have described my invention as embodied'in concrete form and as operating in a specific manner in accordance with the provisions of the patent -statutes, it should be understood that I do not limit my invention thereto, since various modi fications thereof will suggest themselves to those skilled in the art Without departing from the spirit of my invention, the scope of which is set forth in the annexed claims. What I claim as new and desire to secure by Letters Patent of the United States, is:

1. A signal system comprising a continuously rotating shaft located in a receiving station, a rotary indicator, a releasable driving connection between said shaft and said indicator arranged to engage and drive said indicator in a predetermined relation. with said shaft, an electromagnetic device for arresting the rotation of said indicator in oppositionto said driving connection where by said connection is released, and selective means located in a sending station for energizing said electromagnetic device when said indicator has been turned by said shaft to a predetermined indicating position.

2. A signal system comprising a continuously rotating shaft located in a receiving station, a rotary indicator, a yieldable driving connection between said shaft and said rindicator arranged to engage and drive said indicator when said shaft isin a predetermined angular relation therewith, an electroinagnet, a locking member actuated by said electromagnet-for arresting the rotation of said indicator in opposition to said driving nnection, in any one of a plurality of indicating positions whereby said connection 18 released, and selective means located in a sending station for energizing said electromagnet when said indicator has been turned by said shaft to a predetermined indicating position.

3. A signal system comprising two continuously rotating shafts located respectively in sending and receiving stations, means for automatically maintaining said shafts in synchronism, a rotary indicator, a releasable driving connection between said indicator and the shaft in the receiving station arranged to engage and drive said indicator in a definite angular relation therewith, an electromagnetic device form-resting the ro tation of said indicator in opposition to said driving connection in any one of a plurality of indicating positions whereby said connection is released, and selective switching means controlled by the shaft in the sending station for energizing said electromagnet when said indicator has been turned by said shaft to a predetermined indicating position and each revolution thereafter upon reengagement of said driving connection.

4. A signal system comprising two contin uously rotating shafts located respectively in sending and receiving stat-ions, means for automatically maintaining said shafts in synchronism, a rotary indicator mounted on the shaft in the receiving station, a projection on said indicator, a yieldable arm on said shaft engaging said projection so as to normally rotate said indicator in a definite relation with said shaft, anelectromagnetic device for arresting the rotation of said indicator whereby said arm passes over said.

projection releasing said shaft, and selective switching means actuated by the shaft in the sending station for periodically energizing said electromagnetic device once each revolution upon the engagement of said arm with said projection so asto maintain said indicator in a selected position.

5. A signal system comprisingtwo continuously rotating shafts located respectively in sending and receiving stations, means 'for automatically maintaining said shafts in synchronism, a rotary indicator, a releasable driving connection between said indicator and the shaft in the receiving station arranged to engage and drive said indicator in a definite angular relation with said shaft, an electromagnetic device for arresting said indicator in opposition to said driving connection in any one of a plurality of posi tions whereby said connection is released, cooperating switch contacts in the circuit of said electromagnetic device, one of which is rotated with the shaft in the sending station and the other adjustable whereby said electromagnetic device may be energized to arrest said indicator in any one of said positions.

.gaged by said moving contact once each revolution, and an electromagnetic device 15 controlled by said contacts for arresting said indicator in a selected position whereby said, arm passes over said projection releasing said shaft and for subsequently locking said indicator each revolution of its shaft upon 2 the engagement of said arm with said projection.

A In witness whereof, I have hereunto set my hand this 27th day of January 1922.

JOHN L. HALL; 

